For the first time, brittle stars were collected on two seamounts in the Andaman Back-arc Basin. Of the six species, two were new to science and are described herein as Ophioleuce longispinum sp. nov. and Ophiophyllum minimum sp. nov., in the family Ophiuridae, subfamilies Ophioleucinae and Ophiurinae, respectively. Skeletal details were studied and documented by scanning electron microscopy. Morphological similarities between related species are discussed in detail. Ophioleuce longispinum sp. nov. is particularly interesting, because it combines characters typical for its genus with those otherwise only known from Ophiophyllum, such as a limpet-like disc, a fringe of marginal disc papillae or spines, and a paddle-like modified lower arm spine. The remaining species, Astrophiura cf. tiki, Ophiactis perplexa, Ophiolimna antarctica and an unidentified Ophiura, are new records for the Andaman Sea.

Of three intertidal fish species collected on the east coast of South Africa, 67% (127/190) had haemogregarine infections. Horned rockskippers, Antennablennius bifilum Günther, 1861, demonstrated 77% parasite prevalence, maned blennies, Scartella emarginata Günther, 1861, 53% prevalence, and a single specimen of the hotlips triplefin, Helcogramma obtusirostre Klunzinger, 1871, was also parasitized. Less than 1% of A. bifilum and S. emarginata erythrocytes were infected, but ~2% of those of H. obtusirostre. Haemogregarines in A. bifilum and S. emarginata were morphologically similar to H. bigemina Laveran & Mesnil, 1901, but uncharacteristic clusters of four merozoites were observed in S. emarginata and paired gamonts were smaller overall than those of the type species, although close in size to H. bigemina reported elsewhere. Intraerythrocytic gamonts in H. obtusirostre, occurred mainly in fours, a characteristic of the European species originally named H. quadrigemina Brumpt & Lebailly, 1904. Additionally however, this South African species infrequently demonstrated eight intraerythrocytic gamonts and host cells commonly had spiny perimeters and were de-haemoglobulinized. Owing to the differences observed, this species is described as new to science and named Haemogregarina kunegemina sp. nov. Possible haemogregarine developmental stages were found in first and second stage pranizae of the gnathiid isopod, Gnathia pilosus Hadfield, Smit & Avenant-Oldewage, 2008, that had fed on the three fish hosts. These are the first reports of haemogregarines from teleosts of the subtropical east coast of South Africa.

The spatial patterns of distribution of five species of the Gerreidae (Diapterus rhombeus, Eucinostomus argenteus, Eucinostomus gula, Eucinostomus melanopterus and Eugerres brasilianus) in Mambucaba estuary, south-eastern Brazil, were determined to assess habitat partitioning of the estuarine reaches. Sampling was conducted between October 2007 and August 2008. Diapterus rhombeus and E. gula were exclusively found in the lower estuary, whereas E. melanopterus and E. brasilianus were exclusively found from the middle estuary. Eucinostomus argenteus was common in the two estuarine zones. Total length and total weight data showed that the smallest individuals of D. rhombeus and E. gula were found near to the estuarine mouth compared with deeper areas of high salinity and lesser influence of the estuarine plume. The smallest individuals of E. argenteus, E. brasilianus and E. melanopterus were found in a protected estuarine lagoon connected to the main estuarine channel, and the largest in the other sites in the main channel of the middle estuary. Spatial partition seems to be the strategy developed by the 5 members of the Gerreidae family to coexist in the Mambucaba estuary, which may be attributed to competition in the past between the species of Gerreidae or to differentiated tolerance to environmental constraints